President Trump's signature slogan — “America first” — has been tweaked recently by administration aides eager to show that his nationalism is not at odds with the United States' traditional global leadership role. Their new version: "America first does not mean America alone."

Yet America was undeniably alone as Trump on Saturday departed the annual summit of the so-called Group of 20 leaders here. With the leaders' final statement, it was evident that Trump's prioritization of American self-interest — on environmental agreements, trade, migration and more — left him, and thus America, often in unfamiliar isolation.

After two days of cordial smiles, handshakes and back-slapping, Trump expressed satisfaction with the summit. Even so, he was alone among leaders of the world’s major economic powers in dissenting from its resolution affirming the Paris climate accord. And while he has threatened to abandon existing trade deals and penalize countries for what he sees as unfair trade practices, particularly on steel exports, the summit’s closing declaration affirmed support for open markets and fighting protectionism.

After the more exclusive Group of 7 summit in May, German Chancellor Angela Merkel had described the meeting as “six against one” — the one being the United States. As she closed the G-20 gathering that she hosted this week, Merkel again singled out the United States.

In a news conference, Merkel said she “deplores” America’s decision to walk away from the Paris climate agreement and, despite Trump’s comments, does not believe the administration is open to renegotiating the terms agreed to among more than 190 nations to mitigate the effects of climate change.

Merkel, as she has before, called on European countries to step into the vacuum that Trump is leaving on the world stage.

"We as Europeans have to take our fate into our own hands," she said.

The new French president, Emmanuel Macron, who will host Trump next week in Paris to mark Bastille Day, echoed his ally Merkel. “The world has never been so divided,” he said.

In another break from past decades, the United States seemed closer to Russia — in goodwill if not on many issues — than with traditional allies such as Germany and France after Trump’s genial tete-a-tete with President Vladimir Putin, which was the presidents’ first meeting since Trump took office.

Trump’s meeting with Putin, lasting more than two hours, was his longest with any leader. He raised Americans’ concerns over Russian election meddling, according to aides, but the two presidents decided to put the matter behind them and move on to discuss how they can address their differences over Syria, Ukraine and North Korea.

Unlike many other leaders, including Putin, Trump didn’t hold a news conference at the conclusion as American presidents typically have. Putin, in his meeting with reporters, denied again — as he did to Trump on Friday — that Russia interfered in the U.S. election, and said he thinks that Trump accepted his face-to-face denials.

Putin also said that Trump asked him many questions about Russia’s alleged meddling, which Trump has called “a hoax” despite the consensus of American intelligence agencies that Russia did try to sway the election to Trump. FBI and congressional investigations also are probing whether Trump associates colluded with Russia.

White House officials declined to challenge Putin’s view that Trump accepted his denials when questioned by reporters aboard Air Force One en route back to Washington.

Trump "will be happy to make statements himself" about his meeting with Putin, Treasury Secretary Steven Mnuchin said.

He and Trump’s top economic advisor, Gary Cohn, were sanguine about the summit’s results, and singled out as constructive the leaders’ discussions about dumping of cheap raw materials such as steel, limiting migration, and cracking down on terrorist financing.

"These things are never easy — to get 20 of your friends to agree where to have dinner tonight is really hard — but I thought the communique came together pretty reasonably," Cohn said.

For nearly three-quarters of a century, since World War II, the United States has been the preeminent leader in championing open markets and forging a multilateral system of rules to resolve tough international disputes on trade and commerce as well as other issues.

Trump has repeatedly signaled his skepticism of multilateral institutions such as the European Union and forums such as the G-20. In Hamburg, he made little effort to build broad consensus around his populist ideas, instead spending most of his time in private one-on-one discussions with leaders.

The president often left the group’s larger sessions — his daughter, Ivanka, sat in for him at one session Saturday — in favor of such bilateral meetings. Trump had 13 individual meetings with other leaders over three days, including Thursday in Warsaw, the White House said.

Trump and the other leaders of the G-20, whose member nations represent roughly 80% of the world’s economic output, signed off on a joint statement that was seen as an accomplishment given the sharp differences and acrimony stemming largely from Trump’s “America First” agenda.

“We have a G-20 communique, not a G-19 communique,” said one EU official after all-night negotiations to finesse the divisions. But the language on climate change, at least, made plain that the statement was in fact a G-19 communique, with the U.S. alone in opposition.

“They’re calling the statement that they reached a consensus outcome, but it very explicitly points to a deep divide that really undermines the principle of consensus,” said Scott Morris, a senior fellow at the Center for Global Development in Washington and a former Treasury official in the Obama administration.

The declaration’s message on trade was ambiguous, reflecting the “heavy hand of the Trump administration,” said Ricardo Meléndez-Ortiz, chief executive of the International Center for Trade and Sustainable Development in Geneva.

Trump wanted stricter language that allowed countries to punish unfair trade practices. But other leaders would not agree.

“We were able to say, well, markets need to be kept open. This is all about fighting protectionism and also unfair trade practices,” Merkel said.

Other European officials warned the United States was flirting with trade wars.

European Commission President Jean-Claude Juncker said Friday the EU would retaliate swiftly if the U.S. raised trade barriers. “We will respond with countermeasures if need be, hoping that this is not actually necessary,” Juncker said, citing American whiskey as one potential target for import taxes.

Trump was not the only leader at the summit to complain that China is dumping cheap steel into the global market, and the countries commissioned a study on the steel market to be delivered in August.

Migration and refugees, as in recent years, were a focus. According to Cohn, Trump at one session addressed the "downward spiral of migration" and emphasized that "countries should build their own economy, make their own countries a better place for their citizens."

The U.S. pressed for tough language about "the sovereign right of states to manage and control their borders” and had help from the United Kingdom and Italy. Italy especially is facing an unpopular migrant crisis as impoverished refugees displaced by war cross the Mediterranean from North Africa.

U.S. dominance on the global stage had faced challenges before Trump. The rise of other developing nations, chiefly China, has increasingly diminished any single dominant power at events such as the G-20 summit.

And in the past the United States has occasionally waged lone battles, struggling to get a consensus on issues such as currency manipulation, economic stimulus measures and trade surpluses. The G-20 has no power to enforce its will on sovereign nations, so it has sought to find common ground for action and cooperation, with limited success.

Trump seemed to make little headway in Hamburg to enlist other nations to more aggressively confront North Korea’s nuclear threat.

He met with leaders of China, Japan and South Korea, as well as Putin, pressing them at length to come around to his view that North Korea's most recent launch of an intercontinental ballistic missile is a major escalation of Pyongyang’s ambitions as a nuclear power, according to a U.S. official familiar with the talks, who spoke on the condition of anonymity to describe closed-door discussions.

White House officials have been dismayed to see China and Russia teaming up to advocate for a "freeze for peace" strategy in which North Korea agrees to stop moving forward with its nuclear weapons development, in exchange for the international community easing sanctions and making other concessions, the official said.

The administration counters that this strategy has been pursued multiple times with North Korea and each time Pyongyang has cheated and continued to advance toward building a nuclear-capable missile.

Trump avoided major gaffes and seemed to enjoy mingling with his fellow leaders. He did embarrass Mexico's President Enrique Peña Nieto by saying — in the presence of Peña Nieto, as well as Mexican and American reporters — that Mexico will “absolutely” pay for Trump’s planned border wall, something the Mexican leader just as adamantly vowed not to do.

Despite friction with Merkel, Trump thanked her Saturday for hosting the summit even as protesters clashed violently with police at times, burning cars and blocking roads.